Everyone seems to have quite a few hostile bears in their neck of the woods ready to immediately pounce on the first human they see .......
One big advantage the revolver has over the semi-auto in a woods scenario is versatility. You can have a shotshell in the first one or two chambers, a light loaded full wadcutter in the next 2-3 chambers and a full load in the last 2-3 chambers. Multiple rounds for multiple uses, all in one cylinder.
Another reason could be that for many, a .22 rimfire revolver would suffice quite nicely in the woods. Shotshell ability is retained, along with rounds capable of bagging a rabbit or squirrel for the camp stew pot.
As for reliability, semi-autos generally withstand abuse better (like being carried afield) while revolvers withstand neglect better.
The choice depends quite a bit on your intended use. Do you plan on using it to harvest small game? Is it only for protection? If the latter, protection from what? Bear? Wild dogs? Two-legged snakes? Define the mission and the choice becomes easier, if not crystal clear.